Controlled Current Feedback in a Static Inverter with Neutralization of Harmonics

Controlled Current Feedback Transformers (CCFT) are used to achieve optimum efficiency in a transistorized static inverter for the Apollo Command Module. Base-drive is established instantaneously as a predetermined function of collector current and of minimum beta. Techniques for steering the CCFT are incorporated in a circuit which synthesizes in one power transformer a 3-phase, stepped-voltage output of low harmonic content before filtering. A buck-boost voltage regulator is used to accomplish high performance with fewer power transistors.